Separating device

ABSTRACT

Relatively long and therefore valuable textile fibers are separated from an air-borne mixture comprised of such fibers and of smaller particulate matter, such as shorter textile fibers, dust and the like, by a compact but highly efficient separating device of the centrifugal type. The device comprises a cylindrical housing having a diameter to length ratio of preferably approximately 1 to 1.1. Inlet and outlet ducts communicating with the housing are so positioned and proportioned that most of the long textile fibers of the mixture introduced into the housing are discharged at high velocity therefrom through a first outlet duct extending tangentially from the housing, while the remainder of such mixture is discharged through a second outlet duct extending coaxially from the housing. An edge portion of the mouth of the first oulet duct is provided with a relatively large radius of curvature so as to prevent fiber accumulations within the housing.

[451 Sept. 23, 1975 l SEPARATING DEVICE Joseph F. Baigas, Jr., 4901 Sentinel Post Rd., Charlotte, NC. 28211 22 Filed: Dec. 18, 1974 21 Appl. No.: 533,869

[76] Inventor:

[52] U.S. Cl. 209/144; 55/454; 55/459;

55/466 [51] Int. CL? 304C 5/14 [58] Field of Search ..209;144;143;21l; 55/459,

Primary Examiner-Frank W. Lutter Assistant ExaminerRalph .1. Hill Attorney, Agent, or FirmJoseph H. Heard [57] ABSTRACT Relatively long and therefore valuable textile fibers are separated from an air-borne mixture comprised of such fibers and of smaller particulate matter, such as shorter textile fibers, dust and the like, by a compact but highly efficient separating device of the centrifugal type. The device comprises a cylindrical housing having a diameter to length ratio of preferably approximately 1 to 1.1. Inlet and outlet ducts communicating with the housing are so positioned and proportioned that most of the long textile fibers of the mixture introduced into the housing are discharged at high velocity therefrom through a first outlet duct extending tangentially from the housing, while the remainder of such mixture is discharged through a second outlet duct extending coaxially from the housing. An edge portion of the mouth of the first oulet duct is provided with a relatively large radius of curvature so as to prevent fiber accumulations within the housing.

10 Claims, 5 Drawing Figures SEPARATING DEVICE BACKGROUND OF THE INVENTION This invention relates to centrifugal separating and- /or air-cleaning devices, and more particularly relates to the use of such devices in textile mills for the treatment of airborne mixtures of textile fibers, lint, dust and like particulate matter.

Various textile-fiber processing operations, such as the carding operation, generate large amounts of particulate matter of the aforesaid kind. Air-suction apparatus is now customarily used to entrain such matter in an air stream and remove it from the vicinity of the fiber-processing operation. The air-borne particulate matter comprising the output of one or more such apparatuses must then be suitably treated so as to separate the components thereof. Such treatment has heretofore presented certain problems. Treatment by the use of filters alone has not proved successful since the large quantities of particulate matter in the air-home mixture causes rapid loading of the filter devices, with ensuing reduction in treatment efficiency. The use of centrifugal separating devices, either alone or in association with filters, has also been attempted. However, the centrifugal separating devices heretofore proposed for the treatment of airborne mixtures of the type in question usually possess one or more of the following undesirable attributes: (1) Excessive size, particularly in the length direction thereof, and inability to function in other than one specific orientation, which prohibits or impedes their economical installation in many textile mill locations; (2) Large pressure drop, resulting in relatively great operating expense; (3) Non-discrimination, in the separation of the air-borne mixture conducted thereto, between the mixtures valuable and trash components, the former consisting of relatively long textile fibers and the latter consisting of the remaining particulate matter such as dust, lint and the like; and/or (4) Clogging of the devices, with ensuing interruption of their operataion, due to the tendency of particularly the long textile fibers to accumulate upon projections, corners or the like disposed adjacent their paths of travel through the devices. To applicants knowledge, no separating devices intended for the aforesaid purpose have been free from all of the foregoing deficiencies, although solutions to one or more of them have previously been proposed: see, e.g., US. Pat. No. 3,618,303, which discloses a centrifugal separating device wherein the long textile fibers are caused to undergo a change in the direction of their movement during discharge from the device, for the purpose of minimizing the fiber-accumulation problem.

SUMMARY OF THE INVENTION The present invention provides an improved centrifugal separating and/or air cleaning device, particularly adapted for the treatment of large volumes of air containing relatively long textile fibers and smaller particulate matter such as lint and dust, which is free from the deficiencies hereinbefore noted and which efficiently and economically effects separation of most of the long textile fibers from the remaining components of the airborne mixture introduced therein. The device of the present invention is of highly economical and compact construction, the main body portion thereof consisting of a generally cylindrical housing having a diameter to length ratio within the range of approximately 1 to 1.1

2 and preferably in the order of approximately 1 to 1.1. The device may be mounted and used in any desired orientation which, together with its previouslymentioned compact size, facilitates its installation in areas where only a minimum amount of space is available. The device includes an inlet duct and first outlet duct communicating tangentially with the cylindrical housing closely adjacent opposite end walls thereof, and further includes a second outlet duct which projects coaxially into the housing and has its mouth disposed intermediate the length thereof in spaced relationship to both the inlet duct and the first outlet duct. The air-borne mixture undergoing treatment is introduced into the cylindrical housing through the inlet duct at a velocity of preferably at least 3,000 feet per minute. The duct and housing components of the device are so proportioned and positioned relative to one another that most of the long textile fibers contained within the mixture introduced into the housing are centrifugally separated from such mixture and are dis charged through the first outlet duct, together with a minor portion only of the remaining components of the mixture and as little as 2% of the air stream, at a velocity approximately equal to the velocity of the incoming mixture. The mouth of the aforesaid first outlet duct is so configured as to prevent detrimental fiber accumulations thereat. Due to the relatively high velocity and pure content thereof, the long textile fibers sepa rated from the mixture and discharge through the first outlet duct may be readily then conducted to a final recovery area and there collected for subsequent re-use or sale. The lint, dust, and other smaller particulate matter contained in the original mixture introduced into the cylindrical housing, together with most of the entraining air of such mixture, are discharged through the second outlet duct at a velocity equal to approximately one-half of the incoming velocity of the mixture. Due to the almost complete absence of the separately-discharged long textile fibers in the air. discharged through the second outlet duct, such air may readily then be further cleansed by filtration techniques without excessive loading" of the filter device or devices employed. Additionally, the particulate matter filtered from the air during such subsequent cleansing step may be discarded as waste without fear of its containing any significant quantity of relatively long, and therefore potentially valuable, textile fibers.

DESCRIPTION OF THE DRAWING Still other features and benefits of the invention will be apparent from and pointed out in the following description of an illustrative embodiment thereof, which should be read in conjunction with the accompanying drawing, in which:

FIG. 1 is an end view of a separating device constructed in accordance with the invention;

FIG. 2 is a side elevational view of the device, as viewed in direction of the arrows 2-2 of FIG. 1;

FIG. 3 shows the device as viewed from the end thereof opposite to that shown in FIG. 1;

FIG. 4 is a sectional view, taken generally along the lines 44 of FIG. 2, of the device; and

FIG. 5 is an enlarged fragmentary view of one part of the device.

DESCRIPTION OF THE PREFERRED EMBODIMENT The separating device shownv in FIGS. l4 of the drawings includes a cylindrical housing 12 having terminal walls 14, 16 at opposite ends thereof. A transparent viewing port 18 may be provided, if desired and as shown, integrally with and centrally of wall 16. The length of housing 12 is not more than twice the diameter thereof, and the diameter-length ratio is preferably approximately 1 to 1.1, as shown. With the exception of viewing port 18, which if provided would be formed of transparent glass or plastic material, device 10 may be and preferably is formed entirely of wear-resistant sheet metal.

Inlet and outlet means communicating with housing 12 includes an inlet duct 20, a first outlet duct 22, and a second outlet duct 24. Outlet duct 24 is of cylindrical shape and projects coaxially of housing 12 through end wall 14. The terminal open end or mouth 24" of duct 24 is disposed between wall 14and the longitudinal center of housing 12, and preferably is more closely adjacent the former than the latter. The ratio of the crosssectional area of duct 24 to that of housing 12 is within the range of approximately 1 to 4 6 and preferably is approximately 1 to 5.

Inlet duct 20, which preferably is of a rectangular shape as shown, projects tangentially to and through the curved side wall of housing 12 in contiguous relationship to end wall 14. In the length direction of housing 12, duct 20 terminates short of the longitudinal center of housing 12 and of the mouth 24' of cylindrical outlet duct 24. The transverse (vertical, as viewed in the drawing) dimension of inlet duct 20 is no greater than, and preferably is approximately equal to, the difference in the length of the radii of outlet duct 24 and housing 12. The ratio of the cross-sectional area of inlet duct 20 to that of housing 12 is in the approximate range of l to 7 9, and preferably is approximately 1 to 8.

Outlet duct 22 extends tangentially to and through the curved side wall of housing 12 in longitudinallyspaced relationship to ducts 20, 24 and in contiguous relationship to end wall 16 of device 10. Duct 22 is preferably of square or other substantially rectangular cross-sectional shape, and its mouth 26 faces in the direction of spiraling movement, indicated by arrows in the drawing and subsequently described, of the mixture of air and entrained particulate matter introduced into housing 12 through inlet duct 20. The edge portion 28 of mouth 26 which extends transversely of the spiraling direction of movement of the air-borne particulate matter passing thereto has, as is best shown in FIGS. 1 and 5, a large radius of curvature of at least two inches and preferably of approximately two and one-half inches. As shown in the drawing, outlet duct 22 is displaced from inlet duct 20 about the longitudinal axis of housing 12 by approximately 180. However, the magnitude of such displacement may be as great as 360 in the direction of spiraling movement of the air-borne mixture introduced into housing 12 through inlet duct 20. The ratio of the cross-sectional area of duct 24 to that of housing 12 is in the approximate range of l to 60 80, and preferably is approximately 1 to 70. The ratio of the areas of ducts 22, 20 to each other is preferably appro'ximately l to 9.

Device 10 can be used with equal facility in either a positive system, wherein the fan, blower or the like (not shown) which conducts the air-borne mixture to the device is located upstream therefrom, or in a negative system wherein such fan or blower is located downstream from the device. In either case, during operation of device 10 the air-borne mixture to be treated is introduced into housing 12 through inlet duct 20 at a velocity of at least approximately 3,000 feet per minute. After the mixture enters housing 12, it follows a spiraling path extending about the housing axis and toward the opposite end of the housing closed by wall 16 of the device. The long textile fibers of the mixture, which have a greater mass than the lint, dust and other particles within the mixture, are displaced by centrifugal force a greater radial distance from the axis of housing 12, and, upon reaching outlet duct 22, are discharged from housing 12 through duct mouth 26 along with a minor portion only of the smaller particulate matter and the entraining air. More specifically, approximately of the textile fibers having a length of A: inch or more are discharged from-device 10 through duct 22, in conjunction with only approximately 10% of the smaller particulate matter and approximately 2-l0% of the entraining air. The velocity at which the aforesaid long textile fibers are discharged through duct 22 is approximately the same as the velocity at which the mixture is originally introduced into housing 12, i.e., at least approximately 3,000 feet per minute. Such relatively high velocity facilitates the ease with which the discharged long textile fibers can then be conducted to another area (not shown) and there collected for re-use or sale. The majority of the smaller particulate matter and the entraining air within the original mixture introduced into housing 12 does not pass from the housing through outlet duct 22, but rather is discharged therefrom through cylindrical outlet duct 24, at a velocity of approximately one-half of the velocity at which the mixture is originally introduced into the housing through inlet duct 20. Since the entrained material within the air removed from housing 12 through outlet duct 24 consists predominantly of only small particulate matter, and contains only a negligible quantity of long textile fibers, such air can readily be further cleaned, if desired, by one or more filtering devices (not shown) located downstream from outlet duct 24. During their discharge from housing 12 through outlet duct 22, some of the long textile fibers inevitably engage mouth 26 of such duct. However, notwithstanding such engagement and the fact that the fibers are discharged at high velocity without substantial change in the direction of their movement, accumulations of the fibers do not form within mouth 26 or elsewhere in housing 12. The large radius curvature of edge 28 of mouth 26 of outlet duct 22 contributes significantly to the aforesaid desirable result since, but for such large radius of curvature, the relatively long textile fibers would tend to adhere to and accumulate upon edge 28.

Although device 10 is illustrated in the drawing with the longitudinal axis of housing 12 extending generally horizontally, this is for purposes of illustration only. Unlike most other centrifugal separating devices, device 10 can be installed and used with equal facility in any desired orientation. Similarly, and as previously noted, even though inlet duct 20 and outlet duct 22 are illustrated as being displaced from one another about the circumference of housing 12 by approximately 180, such displacement could be of a magnitude up to and including 360. It has also been ascertained that in some installations device will function satisfactory if the locations of inlet duct and outlet duct 22 are reversed, such that inlet duct 20 is contiguous with wall 16 and outlet duct 22 is contiguous with end wall 14 of housing 12. In such a reversed construction, the extent of the inward projection of cylindrical outlet duct 24 into housing 12 preferably would be reduced to approximately one-half of that shown in the drawing.

While a preferred embodiment of the invention has been specifically shown and described, it will be apparent from the foregoing that this was for purposes of illustration only, and not for purposes of limitation, the scope of the invention being in accordance with the following claims.

That which is claimed is: l. A device for separating relatively long textile fibers from an air-borne mixture consisting of said fibers and smaller particulate matters such as lint, dust and the like, comprising:

a generally cylindrical housing having first and second end walls at opposite ends thereof, and having a diameter to length ratio within the range of approximately 1 to 1.1 2.0;

inlet means including an inlet duct extending substantially tangentially to and opening substantially tangentially through the curved side wall of said housing closely adjacent said first of said end walls thereof for introducing said mixture into said housing for passage in a predetermined rotational direction along a spiraling path of travel extending about the axis of said housing and toward said second of said end walls thereof;

first outlet means communicating with said housing for during operation of said device conducting a major portion of said long textile fibers of said mixture and a minor portion only of said smaller particulate matter and of the entraining air of said mixture from said housing at a velocity approximately equal to said velocity at which said mixture is introduced into said housing through said inlet means; said first outlet means including a first outlet duct member extending substantially tangentially from said housing in said predetermined rotational direction and opening substantially tangentially through said curved side wall of said housing closely adjacent said second of said end walls thereof; the mouth of said first outlet duct having an edge portion extending generally parallel to said axis of said housing; and said edge portion of said duct mouth having a radius of curvature of at least approximately 2 inches;

and second outlet means communicating with said housing for during operation of said device conducting therefrom a minor portion only of said long textile fibers and a major portion of said smaller particulate matter and of the entraining air of said mixture at a velocity equal to approximately onehalf of said velocity at which said mixture is introduced into said housing through said inlet means, said second outlet means including a generally cylindrical duct member projecting coaxially of and into said housing through one of said end walls thereof; said cylindrical duct member having an open terminal end disposed within said housing and spaced in the length direction of said housing from both said inlet means and said first outlet means.

2. A device as in claim 1, wherein said cylindrical duct member projects through said first of said end walls of said housing, and the ratio of the crosssectional area of said cylindrical duct member to the cross-sectional area of said housing is within the approximate range of l to 4 6.

3. A device as in claim 2, wherein the ratios of the cross-sectional areas of said inlet duct and of said first outlet duct to the cross-sectional area of said housing are respectively within the ranges of approximately 1 to 7-9and l to60-80.

4. A device as in claim 1, wherein the ratio of the diameter to the length of said housing is approximately 1 to 1.1, and wherein the displacement between said inlet duct and said first outlet duct about the circumference of said housing and in the direction of said spiraling path of travel of said mixture is within the range of approximately 360.

5. A device as in claim 4, wherein said inlet duct and said first outlet duct are each of generally rectangular cross-sectional shape and are contiguous with respective adjacent ones of said first and second end walls of said housing, and wherein the ratio of the crosssectional area of said first outlet duct to said inlet duct is approximately 1 to 9.

6. A device as in claim 5, wherein said inlet duct and said first outlet duct are spaced in the length direction of said housing from each other and from said mouth of said cylindrical outlet duct of said second outlet means.

7. A device as in claim 5, wherein said first outlet duct is of substantially square cross-section shape, and said edge portion of said duct mouth has a radius of curvature of approximately 2% inches.

8. A device as in claim 7, wherein the ratio of the cross-sectional area of said first outlet duct to the crosssectional area of said housing is approximately 1 to 70.

9. A device as in claim 8, wherein the ratio of the cross-sectional area of said inlet duct to the crosssectional area of said housing is approximately 1 to 8.

10. A device as in claim 9, wherein the ratio of the cross-sectional area of said second outlet duct to the cross-sectional area of said housing is approximately 1 toS. 

1. A DEVICE FOR SEPARATING RELATIVELY LONG TEXTILE FIBERS FROM AN AIR-BORNE MIXTURE CONSISTING OF SAD FIBERS AND SMALLER PARTICULATE MATTERS SUCH AS LINT, DUST AND THE LIKE, COMPRISING: A GENERALLY CYLINDRICAL HOUSING HAVING FIRST AND SECOND END WALLS AT OPPOSITE ENDS THEREOF, AND HAVING A DIAMETER TO LENGTH RATIO WITHIN THE RANGE OF APPROXIMATELY 1 TO 1.1 - 2.0, INLET MEANS INCLUDING AN INLET DUCT EXTENDING SUBSTANTIALLY TANGENTIALLYY TO AND OPENING SUBSTANTIALLYY TANGENTIALLY THROUGH THE CURVED SIDE WALL OF SAID HOUSING CLOSELYY ADJACENT SAID FIRST OF SAID END WALLS THEREOF FOR INTRODUCING SAID MIXTURE INTO SAID HOUSING FOR PASSAGE IN A PREDETERMINED ROTATIONAL DIRECTION ALONG A SPIRALING PATH OF TRAVEL EXTENDING ABOUT THE AXIS OF SAID HOUSING AND TOWARD SAID SECOND OF SAID END WALLS THEREOF, FIRST OUTLET MEANS COMMUNICATING WITH SAID HOUSING FOR DURING OPERATION OF SAID DEVICE CONDUCTING A MAJOR PORTION OF SAID LONG TEXTILE FIBERS OF SID MIXTURE AND A MINOR PORTION ONLY OF SAID SMALLER PARTICULATE MATTER AND OF THE ENTRAINING AIR OF SAID MIXTURE FROM SAID HOUSING AT A VELOCITYY APPROXIMATELY EQUAL TO SAID VELOCITYY AT WHICH SAID MIXTURE IS INTRODUCED INTO SAID HOUSING THROUGH SAID INLET MEANS, SID FIRST OUTLET MEANS INCLUDING A FIRST OUTLET DUCT MEMBER EXTENDING SUBSTANTIALLY TANGENTIALLYY FROM SAID HOUSING IN SAID PREDETERMINED ROTATIONAL DIRECTION AND OPENING SUBSTANTIALLYY TANGENTIALLY THROUGH SAID CURVED SIDE WALL OF SAID HOUSING CLOSELY ADJACENT SAID SECOND OF SAID END WALLS THEREOF, THE MOUTH OF SAID FIST OUTLET DUCT HAVING AN EDGE PORTION EXTENDING GENERALLY PARALLEL TO SAID AXIS OF SAID HOUSING, AND SAID EDGE PORTION OF SAID DUCT MOUTH HAVING A RADIUS OF CURVATURE OF AT LEAST APPROXIMATELY 2 INCHES, AND SECOND OUTLET MEANS COMMUNICTING WITH SAID HOUSING FOR DURING OPERATION OF SID DEVICE CONDUCTING THEREFROM A MINOR PORTION ONLY OF SAID LONG TEXTILE FIBERS AND A MAJOR PORTION OF SAID SMALLER PARTICULATE MATTER AND OF TE ENTRAINING AIR OF SAID MIXTURE AT A VELOCITY EQUAL TO APPROXIMATELY ONE-HALF OF SAID VELOCITY AT WHICH SAID MIXTURE IS INTRODUCED INTO SAID HOUSING THROUGH SAID INLET MEANS, SAID SECOND OUTLET MEANS INCLUDING A GENERALLY CYLINDRICAL DUCT MEMBER PROJECTING COAXIALLY OF AND INTO SAID HOUSING THROUGH ONE OF SAID END WALLS THEREOF, SAID CYLINDIRCAL DUCT MEMBER HAVING AN OPEN TERMINAL END DISPOSED WITHIN SAID HOUSING AND SPACED IN THE LENGTH DIRECTION OF SAID HOUSING FROM BOTH SAID INLET MEANS AND SAID FIRST OUTLET MEANS.
 2. A device as in claim 1, wherein said cylindrical duct member projects through said first of said end walls of said housing, and the ratio of the cross-sectional area of said cylindrical duct member to the cross-sectional area of said housing is within the approximate range of 1 to 4 -
 6. 3. A device as in claim 2, wherein the ratios of the cross-sectional areas of said inlet duct and of said first outlet duct to the cross-sectional area of said housing are respectively within the ranges of approximately 1 to 7 - 9 and 1 to 60 -
 80. 4. A device as in claim 1, wherein the ratio of the diameter to the length of said housing is approximately 1 to 1.1, and wherein the displacement between said inlet duct and said first outlet duct about the circumference of said housing and in the direction of said spiraling path of travel of said mixture is within the range of approximately 180 - 360*.
 5. A device as in claim 4, wherein said inlet duct and said first outlet duct are each of generally rectangular cross-sectional shape and are contiGuous with respective adjacent ones of said first and second end walls of said housing, and wherein the ratio of the cross-sectional area of said first outlet duct to said inlet duct is approximately 1 to
 9. 6. A device as in claim 5, wherein said inlet duct and said first outlet duct are spaced in the length direction of said housing from each other and from said mouth of said cylindrical outlet duct of said second outlet means.
 7. A device as in claim 5, wherein said first outlet duct is of substantially square cross-section shape, and said edge portion of said duct mouth has a radius of curvature of approximately 2 1/2 inches.
 8. A device as in claim 7, wherein the ratio of the cross-sectional area of said first outlet duct to the cross-sectional area of said housing is approximately 1 to
 70. 9. A device as in claim 8, wherein the ratio of the cross-sectional area of said inlet duct to the cross-sectional area of said housing is approximately 1 to
 8. 10. A device as in claim 9, wherein the ratio of the cross-sectional area of said second outlet duct to the cross-sectional area of said housing is approximately 1 to
 5. 